It has been a common practice to provide electrical enclosures with knockouts for the connection of conduit fittings and/or wire clamps as required by national and local electrical codes. Common practice has been to provide a large number of small knockouts for individual branch circuits and a larger knockout having one or more succeedingly smaller sized knockouts arranged in a generally concentric or eccentric pattern within the large knockout. The enclosure is generally designed to fit snugly within a standard 16 inch stud wall. Therefore, the number of knockouts and their sizes are generally determined by the dimension of the top and bottom end walls of the enclosure, which must be no larger than 31/2 by 141/2 inches to fit inside the stud wall. The knockouts provided have generally included a large number of small knockouts for 1/2, 3/4 and 1 inch conduit or electrical metallic tubing (EMT), generally used for branch circuits and at least one larger concentric or eccentric knockout for 11/4 to 21/2 inch conduit or EMT, generally used for line conductors or large ampere circuits. When used in commercial applications, electrical codes generally require each branch circuit to be enclosed in some type of electrical conduit or EMT; therefore, a large number of small knockouts for conduit or EMT connections are required. Recent changes in the National Electric Code, for residential applications, now permit a number of Romex type electrical cables (non-metallic sheathed cable) to exit the enclosure through one or more larger openings. Therefore, in residential applications, it is now desirable to have two or more large knockout openings in the endwall rather than one large eccentric knockout and a large number of smaller knockouts. One alternative is to manufacture two electrical enclosures, one having a knockout pattern for commercial use and the other having a knockout pattern for residential use. This alternative requires two different end wall configurations, each having a knockout pattern for a definite purpose enclosure. This is not a desirable solution since it requires the manufacturing and inventory of one enclosure for commercial applications and one enclosure for residential applications. Therefore, it is desirable to produce an enclosure endwall that can meet both the existing commercial requirements and the new residential requirements. However, if the enclosure is intended for both commercial and residential applications, the end wall must have both the large number of small knockouts to meet commercial requirements and more than one large knockout for the new residential requirements.